1. Technical Field
The present invention relates to a magnetic substrate, a common mode filter, a method for manufacturing a magnetic substrate, and a method for manufacturing a common mode filter.
2. Description of the Related Art
As speed and functions of electronic devices tend to increase, the use of an interface for high speed data transmission has increased. Particularly, in a circuit for a high speed interface (USB 2.0, USB 3.0, high-definition multimedia interface (HDMI), or the like) through a differential transmission scheme, a filter for removing common node noise is required.
Recently, as a frequency used for transmitting a signal tends to gradually move to a high frequency band and various portable electronic devices tend to be miniaturized and thinned, research into a small-sized and high-performance common mode filter has been conducted.
The common mode filter is generally configured to include a magnetic layer, a non-magnetic insulator layer, a conductor coil disposed in the non-magnetic layer, a lead terminal wire, and an external electrode connected to the lead terminal wire.
Meanwhile, in order to prevent a rapid change in voltage of the common mode filter, an electrostatic discharge (ESD) protecting element such as a varistor, or the like, has been used in the common mode filter.
A complex electronic component having a configuration in which inductor elements and ESD protecting elements are combined with each other has been disclosed in Patent Document 1.
However, the complex electronic component disclosed in Patent Document 1 is manufactured by simultaneously firing a magnetic material, an electrostatic absorbing layer, and an insulation layer including a conductor pattern. In this case, due to a difference in contraction rate between the respective layers, a problem such as printing bleeding, stack distortion, or the like, occurs, such that characteristics of the common mode filter are deteriorated.